Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

The effective interest rate at the end of the reporting period.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Represents the minimum base rate to be used as the reference rate.

+ References

No definition available.

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- Definition

The extension period for the term of the credit facility.

+ References

No definition available.

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- Definition

Represents the maximum amount of the guarantees available through letters of credit.

+ References

No definition available.

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Debt - Credit Agreement (Details) - USD ($)				9 Months Ended
Debt - Credit Agreement (Details) - USD ($)	Jun. 18, 2020	Apr. 24, 2020	Feb. 12, 2016	Sep. 27, 2020	Apr. 23, 2020	Jun. 18, 2010
Revolving credit facility
Credit Agreement
Unused and available credit under the credit agreement				$ 533,800,000
Stand-by letters of credit outstanding				$ 16,200,000
Letters of credit
Credit Agreement
Term of debt				1 year
Stand-by letters of credit outstanding				$ 16,200,000
Credit Agreement
Credit Agreement
Borrowing capacity		$ 100,000,000
Term of debt			5 years
Sublimit on letters of credit			$ 100,000,000
Eurocurrency rate loans \| LIBOR
Credit Agreement
Minimum base rate (as a percent)		$ 1.00
Eurocurrency rate loans \| LIBOR \| Minimum
Credit Agreement
Interest rate added to base rate (as a percent)		1.50%
Eurocurrency rate loans \| LIBOR \| Maximum
Credit Agreement
Interest rate added to base rate (as a percent)		2.10%
Base rate loans and swing line loans
Credit Agreement
Minimum base rate (as a percent)		$ 2.00
Base rate loans and swing line loans \| LIBOR
Credit Agreement
Interest rate (as a percent)		1.00%
Base rate loans and swing line loans \| Prime Rate
Credit Agreement
Interest rate (as a percent)		0.50%
Revolving credit facility
Credit Agreement
Borrowing capacity		$ 800,000,000	$ 500,000,000		$ 500,000,000
Extension period		1 year
Interest rate on revolving credit facility (as a percent)				2.50%
Amount drawn				$ 250,000,000.0
Term loan facility \| Term Loan due February 2021
Credit Agreement
Term of debt			5 years
Face amount			$ 300,000,000
Amount drawn				$ 300,000,000
Notes Purchase Agreement 2010 \| Revolving credit facility
Credit Agreement
Repayment of debt	$ 35,000,000.0
Notes Purchase Agreement 2010 \| Senior notes
Credit Agreement
Face amount						$ 75,000,000.0
Amount drawn	$ 40,000,000.0
Swing Line Loans
Credit Agreement
Borrowing capacity		$ 15,000,000